Problem: Subtract.
Solution: There are many ways to solve this problem. Let's see two ways we can solve it. Place Value We can think in terms of tenths: $\begin{aligned} &\phantom{=}1.1 - 0.5\\\\ &=11\text{ tenths} - 5\text{ tenths}\\\\ &=6\text{ tenths}\\\\ &=0.6 \end{aligned}$ Place value table Let's line up the numbers by their decimal places. Ones $.$ Tenths ${1}$ $.$ ${1}$ $0$ $.$ ${5}$ Now, let's subtract each place value column. Ones $.$ Tenths $\overset{0}{\cancel{{1}}}$ $.$ $\overset{11}{\cancel{{1}}}$ $-$ ${0}$ $.$ ${5}$ $\underline{~~~~}$ $\underline{~~~~}$ $\underline{~~~~}$ $0$ $.$ $6$ $0.6=1.1 - 0.5$